Repressed Memories

1. Repressed Memories Elizabeth Loftus

2. Recalling Episodic Memory • Recall is a generative processes rather than simply calling up stored data

3. Recalling Episodic Memory • Recall is a generative processes rather than simply calling up stored data • Evidenced by the fact that episodic memories can be distorted or completely false under certain circumstances

4. Recalling Episodic Memory • Misinformation Effect - exposure to information subsequent to storage of memory can alter the contents of the memory

5. Recalling Episodic Memory • Misinformation Effect • Consider the following example: • Subjects were shown a video depicting a car accident • Then given the following question: “How fast were the vehicles going when they ______” • Different subjects were asked questions that differed in the “magnitude” of the final word • The possible words were: Contacted, Hit, Bumped, Collided, and Smashed

6. Recalling Episodic Memory • Misinformation Effect • Consider the following example: • Average estimated velocity depended on the nature of the question

7. Recalling Episodic Memory • Misinformation Effect • Interpretation: • Episodic memory can be distorted by subsequent information

8. Recalling Episodic Memory • False Memories may arise when details of a crime are in question as in eye-witness testimony or repressed memories of abuse during childhood What is the distinction between a false memory and a distorted memory? What do they have in common?

9. “Derepressed memories” • Loftus opens with several examples of court cases that involve “derepressed memories” • What is a repressed memory? • What is a derepressed memory?

10. Loftus’ position in this article • Loftus does not reject the notion of repressed memories • 18% - 59% of abuse survivors report having regained access to previously repressed memories

11. Loftus’ position in this article • Loftus does not reject the notion of repressed memories • 18% - 59% of abuse survivors report having regained access to previously repressed memories • What does Loftus challenge?

12. Loftus’ position in this article • Loftus does not reject the notion of repressed memories • 18% - 59% of abuse survivors report having regained access to previously repressed memories • What does Loftus challenge? …That all “de-repressed” memories are accurate memories.

13. Survivor of real abuse might struggle for years or decades with consequences and need to confront the repressed memory in order to recover emotionally False accusation could tear family apart and send an innocent person to jail High Stakes

14. What’s the issue? • What does Loftus express concern about regarding the derepression of memories?

15. What’s the issue? • What does Loftus express concern about regarding the derepression of memories? • reality of the memory is in question if it is recalled under certain circumstances

16. What’s the issue? • What does Loftus express concern about regarding the derepression of memories? • reality of the memory is in question if it is recalled under certain circumstances • What is the course of events that Loftus finds worrisome?

17. What’s the issue? • What does Loftus express concern about regarding the derepression of memories? • reality of the memory is in question if it is recalled under certain circumstances • What is the course of events that Loftus finds worrisome? This memory might be false! Therapist or Popular Book suggests that patient consider possibility of abuse An explicit episodic memory is achieved Patient engages in intense effort to recall

18. What’s the issue? • So we potentially have a situation in which someone who is having troubles in life and is seeking answers is told to determine whether or not memories for abuse exist • What are some techniques that are used to “assist” recollection?

19. What’s the issue? • So we potentially have a situation in which someone who is having troubles in life and is seeking answers is told to determine whether or not memories for abuse exist • What are some techniques that are used to “assist” recollection? • hypnosis, imagery, dream analysis, story telling • Loftus presents evidence that such processes may lead to invalid memories or overconfidence in the validity of memories

20. Conclusion: • We cannot know with certainty (without corroborating evidence) whether a derepressed memory is true • Therapists should engage in probing this possibility very carefully • avoiding suggestive questions • remaining unconvinced without corroborating evidence • being “gently confrontational” to encourage patient to consider the possibility that the events didn’t happen

21. Subconscious Cognition?! What you don’t know, might help you…or it might not!

22. Perception and Cognition • We have elaborate perceptual mechanisms to provide information to our brains to guide current or future behavior

23. Perception and Cognition • We have elaborate perceptual mechanisms to provide information to our brains to guide current or future behavior • Notice there’s no mention of consciousness

24. Perception and Cognition • We have elaborate perceptual mechanisms to provide information to our brains to guide current or future behavior • Notice there’s no mention of consciousness • Lot’s of information gets processed and used by your brain without you noticing

25. Perception and Cognition • We have elaborate perceptual mechanisms to provide information to our brains to guide current or future behavior • Notice there’s no mention of consciousness • Lot’s of information gets processed and used by your brain without you noticing • Consider some examples

26. Blindsight and the Dorsal Stream • Lesions (usually due to stroke) in primary visual cortex cause a region of blindness called a scotoma • Identified using perimetry X

27. Blindsight and the Dorsal Stream • Patients with lesions to primary visual cortex occasionally retain some visual abilities: • better than chance performance on forced-choice discrimination tasks • spatial navigation and coordination (i.e. avoid obstacles, interact with environment)

28. Blindsight and the Dorsal Stream • Patients with lesions to primary visual cortex occasionally retain some visual abilities: • better than chance performance on forced-choice discrimination tasks • spatial navigation and coordination (i.e. avoid obstacles, interact with environment) • Thought to be because of other “backdoor” pathways that send signals to the Dorsal Stream, A.K.A the “Where and How Pathway”

29. “WHERE” “WHAT” Blindsight and the Dorsal Stream • The Dorsal Stream is thought to mediate much spatial processing and interaction with the environment

30. Blindsight and the Dorsal Stream • The Dorsal Stream is thought to mediate much spatial processing and interaction with the environment • But the neural activity in these structures does not (is not alone sufficient to) enter into consciousness

31. Object Substitution Masking • Masking occurs when one stimulus impairs perception of a nearby stimulus • In special cases the stimuli don’t have to overlap in space or time!? • Object substitution masking occurs when attention cannot select a target object before it vanishes …AND… • A mask is visible at the target location after the target has vanished

32. Object Substitution Masking

33. Object Substitution Masking • Surprisingly, some visual information survives masking • Subjects are accurate at reaching to grasp a masked shape even though they can’t consciously see it

34. Masked Priming • Surprisingly even the meaning of visual information can survive some kinds of masking

35. Masked Priming S P A M TIME

36. Masked Priming XXXXX S P A M TIME

37. Masked Priming S P _ _ XXXXX S P A M TIME

38. Masked Priming • Subject must complete the stem to make any word other than the word that was masked

39. Masked Priming • Subject must complete the stem to make any word other than the word that was masked • Subjects are more likely to use masked word…indicates subconscious influence on behavior

40. The Hard Problem Returns • MYSTERY: what is special about neural activity that leads to awareness ? NOBODY KNOWS !